Manoeuvering or operating devices



y 1958 GUSTAV (GSTA) ADOLF FORSBERG 2,841,120

MANOEUVERING OR OPERATING DEVICES Filed Sept. 13, 1955 3 Sheets-Sheet 1 July' l, 1958 GusTAv (GSTA) ADOLF FORSBERG &

MANOEUVERING OR OPERATING DEVICES 3 Sheets-Sheet 2 Filed Sept. 13, 1955 y 1958 GUSTAV (Gs'A) ADOLF'FORSBERG &

- MANOEUVERING OR OPERATING DEVICES Filed Sept. 13, 1955 3 Sheets-Sheet 3 United ,States Patett O MANOEUVERING OR OPERATING DEVICES Gustav (Gsta) Adolf Forsberg, Sandviken, Sweden Application September 13, 1955, Serial No. 534,088 Claims. (Cl. 121-46) The present invention relates to an Operating or manoeuvering device which is specially suitable for loading and shovelling machines ,comprising a piston reciprocating in a cylinder. I

Such Operating devices have previously been used in such machines. Such loading machines are normally mounted on a tractor. and comprise an arm, swingably connected to the tractor and carrying a shovel supported I by ,a double armed lever which is pivotally mounted on `backs of the known devices.

It is another object of the present invention to provide an Operating device for changing the distance between two hearing members spaced apart from each other which device comprises a cylinder and a piston reciprocating therein, the cylinder and piston being arranged in such manner that pressure exerted upon the free side of the piston reduces the distance between the bearing members 'while pressure upon the piston rod carrying side of the piston increases such distance.

It is still a further object of the present invention to provide an Operating device for a loading machine including a shovel, which device comprises a cylinder and a piston reciprocating therein, and a lever pivotally mounted on a lifting arm, said piston being connected with one end of the lever in such manner that the shovel is disposed opposite the free side of the piston, while the bearing member rigidly Secured to the loading machine is disposed on the piston rod carrying side of the piston.

With these and other objects in view which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawings, in which:

Figure 1 is a side elevation of a tractor with a loading device of conventional structure;

Fig. 2 is a side elevation, partly in section, of the operating means for a loading device of Fig. 1;

Fig. 3 is a side elevation, partly in section, of the operating device according to the present invention;

Fig. 4 is a plan view, partly in section, the device shown in Fig. 3;

Fig. 5 is a section along the lines 5--5 of Fig. 3', and

Fig. 6 is a section along the lines 6--6 of Fig. 3.

Referring now to the drawings, and particularly to Figs. 1 and 2, an Operating device as used in conventional loading machines is disclosed. The loading machine is normally mounted on a tractor and comprises an arm 1 swingeffective' arm of which is much smaller.

1 is to be lifted, the pressure fluid exerts its maximum, force upon the piston, an arrangement which is desirable Patented July 1, 1958 ably connected to the tractor and carrying a shovel 2 supported by a double armed lever 3 which is pivotally mounted on the arm 1. Two hydraulically operated devices 5 and 6, serve the purpose of lifting and lowering, respectively, the arm 1 and the shove12, respectively.

As may be readily seen, in order to lift the arm 1 a pressure fluid is supplied through the tube 7 to one end of the cylinder of the device 5, whereas pressure fluid is ejected through the tube 8 at the other end of the cylinder. When the arm 1 is lowered the process is reversed, i. e., pressure fluid enters through the tube 8 and fluid is ejected through the tube 7. When the arm 1 is lifted, pressure is exerted upon that side of the piston of the device 5 which is opposte the piston rod and which has a larger effective area than the *other piston side, the

and bringing about the best efect. If it is assumed that the pump delivering the pressure fluid works at a predetermined rate, it is also possible to provide an arrangement in which the lifting of the arm 1, which is obviously, by far, a heavier operation than its lowering, is performed by great force and a certain moderate speed, while the\ lowerng of the arm is performed by a moderate force,

ly here also is the heaviest operation, pressure is exerted e upon the less effective side of the piston of the device 6, i. e. the side where the piston rod is connected, by pressure fluid supplied through a tube 9. The lifting is therefore performed only by a moderate force. When the shovel 2 is to -be lowered or emptied, i. e. swung clockwise in Fig. 1, this is performed by supplying the fluid through the tube 10 and removing fluid through the tube 9, in other words, pressure is exerted upon the fred area of the piston, whereby the operation is performed by great force.

These drawbacks could naturally be obviated by arranging the Operating device 6 under or below the arm 1, i. e., being in engagement with the shaft 3 or the shovel 2 on the other side of the fulcrum point 4. Such an arrangement would, however, involve still greater disadvantages due to the lack of space and other obvious drawbacks, and it can, therefore, not be adapted. In order to reduce, at leasta little, the disadvantageous influence of the "position" of the piston rod of the Operating device 6, the diameter of the part 11 of the piston rod which is directly cooperating with the cylinder is usually reduced as indicated in Fig. 2, but this measure while improving slightly the operation, is not a satisfactor'y solution to the present problem. a

Referring now to Figs. 3 to 6 of the drawing where an Operating device in accordance with the present invention is'disclosed, sleeve-formed bearing members 12 and 13 or' the like for mounting the Operating device in engagement with elements to be lifted, e. g., the lever 3 of the shovel 2 and the arm 1 of the loading machine (Fig. l), are provided, the distance 'between the hearing members 12 and 13 being increased and decreased, respectively, by means of the Operating device. Two plate formed parts 14 and 15 are fastened to the hearing member .12 and to these parts is in turn fastened, suitably by welding or soldering or brazing, one cylinder head or cover 17 of the cylinder 16 of the device. The cylinder head 17 and a second cylinder head 18, disposed at the other end of the cylinder When the arm 16; are advantageously intel-connected by tension rods or I drag bars I& or the like Fgs, 5and 6). In the embodi-- ment shown in the drawing, the cylinder heads 17 and 18 have a square form, the tension rods 19 being arranged preferably 'ati the; corners of the cylinder heads; In the cylinder, ,there is in the conventional manner (by 'influence ofi-pressurefluidmeciprocating a piston 20with a piston rQd21'projecting through and'sealing against the cylinder head 17 disposed nearest to the member 12. The pistonrodzl has fastened thereto. across-head 22 which togethen with thepiston rod` 21' forms a T. On the end faces 23 and 24` of the cross-head 22 are mounted one of the endsof two rods-or links ZS-and 26, respectively, the other ofthe= ends of whichare rigidly fastened" to the bearing member 13'; In:ord`er to=increasethe rgidity of the rods 25, 26, two stiffening-plates orstruts 27`and 28 are arranged` betweenthem;

. As will 'be-apparent from theabove description the bearng member'13 conneoted to the piston rod 21 isdisposed on'that sid'e of the cylinder 16 which is opposite the piston rod 2l`, whle= the` hearing member; 12 connected to the cylinder 16-is Situated on; the same side of the cylinder asis-'the piston rod 21. This arrangement which can be said' to be reversed, as compared with the conventional arrangement, shown in Fig. 2, offers very remarkable advantages. By supplying pressure fluid through a tube connection 29 to the-cylinder 16 to the right of the piston 21 inFigs. 3 and 4, a reduction of the distance between the members 12 and 13 and, thereby, of parts connected thereto, is obtained; Atthe operation for reducing the distance between the-bearing members, the effective free area of the piston is in operation and not reduced by the piston-rod ass the case intheknown device shown in Fig. 2. When using the manoeuvering or Operating device accordingto the present invention, shown in Figs. 3-6, instead of the device sshown in Fig. 1 and disposed above the-arml, the full or maximum force and the greatest torque or turning moment are obtained at the heavy operation, i; e., when* the shovel 2 is lfted or swung counter-clockwise` in Fig; 1. That the operation at a certain predetermined pump speedtis performed at a relatively moderate speed is likewise an advantage. At the light' operation, i. e', when the shovel is lowered or swung clockwise in Fg. 1 ai faster movement of the shovel is obtained at an unchangeable' pump speed The emptying of the contents of' the-shovel2` as well asof the pressure fluid in the cylinder 16, at the right of piston 20 in Figs. 3 and' 4 are thus' performed rapidly which is desirable because of the saving of time.

A further great: advantage of the present' invention resides in the fact that the' cylinder head 18 is* readily removable, e. g. when the; piston 20 or-packirgs of the piston 20'shall be-replaced or when other maintenance work or inspectionsmust beperformed; The corresponding cylinder head' of. the" hitherto used devices is' not'removable but fastened to one of the hearing members, asmay be seen in= Fig. 2, in. which the head'31 is secured to thebearing member 32. An exchange of the packngs has, therefore, hitherto been considerable work.

Itisobvious that the` present invention is not limited to the embodiments described-aboveand shown in the accompanyng drawings, since. other embodiments are possiblewithin the scope of'the invention. Thus other con&

necting elementsuor-devicesbetweenthe bearing-memben 12 and the cylinder 16 or the bearing member 17 and the pistonrod21 may be used instead of the plates^1'4* and the rods and 26, respectively. Further one or both of the cylinder heads 17 and 18 may be mounted in deliberate or arbitrary manners other than shown.

The piston rod 21, which for obvious reasons is rather sensitive, is well protected against blows or shocks, by the parts 14, 15, 22, 25 and`26which are surrounding the i may be such'that' the parts have a relatively small mutual play, e. g., 0.1-0.5 mm., which may be filled up with sealing lubricants. The rods 25 and 26 which may be of U-profile and the width and thckness, respectively, of the cross-head 22 are then substantially the same as the distance between the plates 14 and 15.

While I'` have disclosed several embodiments of the present' invention, it is to be' understood that these embodments aregiven by example only'and not' in a lmiting sense, the scope of the present invention being determined bythe objects and the claims; a

I claim:

l-L A devce for changing the distance between two bearing members comprising a cylinder, first means for pivotally connecting said cylinder in one of said hearing members, and a piston reciprocating in said cylinder and Secured to a pistorr rod, secondmeans for conn'ecting said piston rod with the other'of'said' bearng members, said. first connecting means comprisng' a pair of plates disposed in substantally parallel planes spaced apart from each' other, one end' of" each of said plates being Secured to said one of said hearing members and the other end of each'of said-plates being secured to said cylinder; and' said second connecting means comprising a pair of rods spaced apart from each other and a cross-head connecting opposite ends of said rods and Secured to the free end of said piston rod, said cross-head reciprocating together with said piston rod betweensaid plates axially, and said one of said bearing members being stationary While the other of said hearing member changes its distance-from said one` of said' hearing members responsive to. the. position` of. said' piston in said cylinder.

2. The device, as set forth in claim 1, in which said cross-head moves along a path between said' one of 'said hearing members and the head of' said cylinder remote from said other of said bearing members.

3. The device, as set forth in claim 1', in which said plates are rigidly connected to said cylinder.

4; The device, as set forth in claim 1, in which said' plates and said rods are of respective cross sections to form guides relative to each other.

5. The device, as setforth in claim 1, in which said plates and said rods complement each other to form a cover for 'said piston rod durngithe reciprocating movement of the latter.

References Cited in the file of this patent UNITED: STATES PATENTS 

